In order to be able to precisely measure an original or presently machined diameter of a clamped work piece during a manufacturing process and in order to be able to adjust the subsequent machining accordingly it is already known to provide a turning machine with a measuring device with a measuring scanner which performs the measuring of the work piece through mechanical contact scanning or through optical scanning.
In conventional turning machines in which the head stock for driving the work piece is permanently mounted to a bed or moveable at the most in the Z-direction, the rotation axis, such measurement scanners were typically mounted on the bed moveable in X-direction in order to be able to move to the diameter to be measured until a contact is established and they were additionally moveable in Z direction in order to be able to measure at different axial positions.
Thus the employed mechanical measuring scanners preferably also protruded from their holders in the measuring direction, thus typically in X-direction against the axis of rotation.
This way, however, the radius of the work piece with respect to the rotation axis can only be measured in one direction.
When two measuring devices of this type were mounted in a conventional turning machine on two transversal directions arranged opposite to one another, e.g. a positive and a negative X-direction, a diameter e.g. of a crank shaft journal could be measured in the same rotational position of the work piece, however a sum of errors of both measuring devices was included in the measuring result and additional complexity was created through two measuring devices and a common computing contd.